package com.example.basicquestions.questions.对称字符串;

import com.sun.xml.internal.ws.api.model.wsdl.WSDLOutput;

import java.util.Scanner;

public class Main{

    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);
        int t = sc.nextInt();

        for(int i = 0; i <t; i++) {
            long n = sc.nextLong();
            long k = sc.nextLong();

            long count = (long)Math.pow(2,n-1);
            long res = recursion(count,k,0);
            if(res%2 == 0) {
                System.out.println("red");
            }else{
                System.out.println("blue");
            }
        }
    }
    public static long recursion(long count,long k,long reverse) {
        if(count == 1){
            return reverse;
        }
        long half = (count)/2;
        if(k < half){
            reverse++;
            return recursion(half,k,reverse);
        }else {
            return recursion(half,k-half,reverse);
        }
    }
}